DESCRIPTION (Investigator's Abstract): As biotechnology discovers more and more bioactive peptides and proteins, the quest for a non-injection way to deliver them into the body has intensified and is now focused sharply on the lungs. Unlike the oral, nasal and transdermal routes of delivery, new research is showing the lungs to be naturally permeable to a variety of therapeutic macromolecules (i.e. growth hormone, insulin, interferon, granulocyte colony stimulating factor, etc.). Large pharmaceutical programs for the development of aerosol protein products are now being initiated with insulin the most advanced in human trials. While small molecule drugs have been inhaled for years for the management of asthma, chronic inhalation of therapeutic proteins is a brand new field. The biological and immunological consequences of chronic pulmonary exposure to exogenous macromolecules are uncertain. So far, safety studies with a number of peptides and proteins suggest that chronic inhalation of small amounts of peptide or protein can be safe. The meeting aims to bring together for the first time, widely separate groups of scientists from industrial and academic fields including drug delivery scientists, pharmacologists, inhalation toxicologists, and pulmonary immunologists. The goal of the meeting is to present the latest available pharmaceutical data on pulmonary protein delivery and safety, side by side with the state-of-the-art in pulmonary immunology as it relates to tolerance and reaction to exogenous protein exposure.